| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.apex.malhar.lib.window.sample.pi; |
| |
| import org.joda.time.Duration; |
| |
| import org.apache.apex.malhar.lib.io.ConsoleOutputOperator; |
| import org.apache.apex.malhar.lib.window.Accumulation; |
| import org.apache.apex.malhar.lib.window.TriggerOption; |
| import org.apache.apex.malhar.lib.window.Tuple; |
| import org.apache.apex.malhar.lib.window.WindowOption; |
| import org.apache.apex.malhar.lib.window.WindowState; |
| import org.apache.apex.malhar.lib.window.impl.InMemoryWindowedStorage; |
| import org.apache.apex.malhar.lib.window.impl.WindowedOperatorImpl; |
| import org.apache.commons.lang3.mutable.MutableLong; |
| import org.apache.commons.lang3.tuple.MutablePair; |
| import org.apache.hadoop.conf.Configuration; |
| |
| import com.datatorrent.api.DAG; |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.api.InputOperator; |
| import com.datatorrent.api.LocalMode; |
| import com.datatorrent.api.StreamingApplication; |
| import com.datatorrent.common.util.BaseOperator; |
| |
| /** |
| * This is an example of using the WindowedOperator concepts to calculate the value of pi. |
| */ |
| public class Application implements StreamingApplication |
| { |
| public static class RandomNumberPairGenerator extends BaseOperator implements InputOperator |
| { |
| public final transient DefaultOutputPort<Tuple<MutablePair<Double, Double>>> output = new DefaultOutputPort<>(); |
| |
| @Override |
| public void emitTuples() |
| { |
| Tuple.PlainTuple<MutablePair<Double, Double>> tuple = new Tuple.PlainTuple<>(new MutablePair<>(Math.random(), Math.random())); |
| this.output.emit(tuple); |
| } |
| } |
| |
| public static class PiAccumulation implements Accumulation<MutablePair<Double, Double>, MutablePair<MutableLong, MutableLong>, Double> |
| { |
| @Override |
| public MutablePair<MutableLong, MutableLong> defaultAccumulatedValue() |
| { |
| return new MutablePair<>(new MutableLong(0), new MutableLong(0)); |
| } |
| |
| @Override |
| public MutablePair<MutableLong, MutableLong> accumulate(MutablePair<MutableLong, MutableLong> accumulatedValue, MutablePair<Double, Double> input) |
| { |
| if (input.getLeft() * input.getLeft() + input.getRight() * input.getRight() < 1) { |
| accumulatedValue.getLeft().increment(); |
| } |
| accumulatedValue.getRight().increment(); |
| return accumulatedValue; |
| } |
| |
| @Override |
| public MutablePair<MutableLong, MutableLong> merge(MutablePair<MutableLong, MutableLong> accumulatedValue1, MutablePair<MutableLong, MutableLong> accumulatedValue2) |
| { |
| accumulatedValue1.getLeft().add(accumulatedValue2.getLeft()); |
| accumulatedValue1.getRight().add(accumulatedValue2.getRight()); |
| return accumulatedValue1; |
| } |
| |
| @Override |
| public Double getOutput(MutablePair<MutableLong, MutableLong> accumulatedValue) |
| { |
| return accumulatedValue.getRight().longValue() == 0 ? 0.0 : (((double)accumulatedValue.getLeft().longValue()) * 4 / accumulatedValue.getRight().longValue()); |
| } |
| |
| @Override |
| public Double getRetraction(Double value) |
| { |
| return -value; |
| } |
| } |
| |
| @Override |
| public void populateDAG(DAG dag, Configuration configuration) |
| { |
| RandomNumberPairGenerator inputOperator = new RandomNumberPairGenerator(); |
| WindowedOperatorImpl<MutablePair<Double, Double>, MutablePair<MutableLong, MutableLong>, Double> windowedOperator = new WindowedOperatorImpl<>(); |
| Accumulation<MutablePair<Double, Double>, MutablePair<MutableLong, MutableLong>, Double> piAccumulation = new PiAccumulation(); |
| |
| windowedOperator.setAccumulation(piAccumulation); |
| windowedOperator.setDataStorage(new InMemoryWindowedStorage<MutablePair<MutableLong, MutableLong>>()); |
| windowedOperator.setWindowStateStorage(new InMemoryWindowedStorage<WindowState>()); |
| windowedOperator.setWindowOption(new WindowOption.GlobalWindow()); |
| windowedOperator.setTriggerOption(TriggerOption.AtWatermark().withEarlyFiringsAtEvery(Duration.millis(1000)).accumulatingFiredPanes()); |
| |
| ConsoleOutputOperator outputOperator = new ConsoleOutputOperator(); |
| dag.addOperator("inputOperator", inputOperator); |
| dag.addOperator("windowedOperator", windowedOperator); |
| dag.addOperator("outputOperator", outputOperator); |
| dag.addStream("input_windowed", inputOperator.output, windowedOperator.input); |
| dag.addStream("windowed_output", windowedOperator.output, outputOperator.input); |
| } |
| |
| public static void main(String[] args) throws Exception |
| { |
| LocalMode lma = LocalMode.newInstance(); |
| Configuration conf = new Configuration(false); |
| lma.prepareDAG(new Application(), conf); |
| LocalMode.Controller lc = lma.getController(); |
| lc.run(); |
| } |
| } |